Performance of virgin and refined avocado oils during deep-frying and thermoxidation simulating frying in comparison with olive and sunflower oils

Abstract

Avocado oil stability at frying temperatures has been scarcely studied. In this work, the performance of virgin (VAO), minimally refined (MRAO) and refined (RAO) avocado oils was evaluated in deep-frying and thermoxidation experiments in comparison with sunflower (SO), high-oleic sunflower (HOSO), and virgin olive (VOO) oils. Polar compounds, polymers and tocopherols were determined. For all oils, no significant differences in polymers levels were found after 10h thermoxidation and 9 discontinuous deep-frying operation. The most stable oils were HOSO, VAO, VOO and MRAO, all showing less than 20% polar compounds after 9 frying operations. Besides the stability conferred by the predominant monounsaturated fatty acids (oleic acid), the better frying performance shown by these four oils was attributed to the high content of tocopherols and DMPS in HOSO, and the presence of protective minor compounds in virgin oils (VAO and VOO) and MRAO.

Keywords

• Avocado oil
• Frying
• Olive oil
• Refining
• Sunflower oil
• Thermoxidation